In this technical field of forming containers, hygiene is a very important issue in order to prevent any risk of contamination of the content of the containers, for example bottles with products that are to be ingested by consumers or applied on the skin of a consumer. Consequently, the cleaning of the stations for forming the containers and of their components is a fundamental issue.
In such stations, the injection assembly comprises at least a movable outlet in order to allow easy placing of a preform in the station and retrieving of a formed container from the station and to allow placing the outlet of the injection device in fluidic communication with the preform to inject the fluid inside the preform. To this end, the outlet is made part of a housing which is movable relative to a main body, for example formed by a carrousel, and which is able to receive the fluid from a fluid source via an injection device, attached to the main body and arranged to inject the fluid inside the movable housing to the outlet. In order to prevent any leaking of fluid between the movable housing and the main body and to ensure a proper flow of the fluid between the source and the outlet, sealing means are needed between the movable housing and the main body. Documents WO-2010/003873 and EP-1 529 620 for example disclose such injection devices.
For such injection devices, dynamic sealing means are necessary. These dynamic sealing means provide liquid tight contact between the main body and the sliding housing. For example, some dynamic seal means may include seal rings maintained in place inside a circular receiving groove of the main body. As the movement of the housing has to be allowed, the seal ring can move inside the receiving groove. The dynamic sealing means are in contact with the fluid to be injected, are hard to clean. Cleaning of dynamic sealing means may require a dismantlement of the injection device or several inlets for cleaning products, in order to ensure that the cleaning products properly reach and clean the sealing means. For example, the receiving groove may be a bacteria trap and cleaning it may require to remove the seal rings. Consequently, the cleaning of the injection device is complicated and time consuming, which reduces the throughput of the station.
Document US 2012/0315350 shows a station comprising a blow nozzle and a pressure source movable between a retracted position and an injection position, wherein the blow nozzle forms a seal on the finish of the preform. However, this document does not specify how the blow nozzle is moved between the retracted position and the injection position.
One of the aims of the invention is to simplify the cleaning of an injection assembly and guarantying a proper cleaning of all its components via a single cleaning path and without having to dismantle the injection device. Another aim of the invention is to provide an injection assembly able to sustain high pressures of liquid flowing in the injection assembly.